Effects of diabetes on the vascular system: current research evidence and best practice recommendations

Inhibition of PHLPP1 ameliorates cardiac dysfunction via activation of the PI3K/Akt/mTOR signalling pathway in diabetic cardiomyopathy

Background

Pleckstrin homology (PH) domain leucine‐rich repeat protein phosphatase 1 (PHLPP1) is a kind of serine/threonine phosphatase, whose dysregulation is accompanied with numerous human diseases. However, its role in diabetic cardiomyopathy remains unclear. We explored the underlying function and mechanism of PHLPP1 in diabetic cardiomyopathy (DCM).

Method

In vivo, Type 1 diabetic rats were induced by intraperitoneal injection of 60 mg/kg streptozotocin (STZ). Lentivirus‐mediated short hairpin RNA (shRNA) was used to knock down the expression of PHLPP1. In vitro, primary neonatal rat cardiomyocytes and H9C2 cells were incubated in 5.5 mmol/L glucose (normal glucose, NG) or 33.3 mmol/L glucose (high glucose, HG). PHLPP1 expression was inhibited by PHLPP1‐siRNA to probe into the function of PHLPP1 in high glucose‐induced apoptosis in H9c2 cells.

Results

Diabetic rats showed up‐regulated PHLPP1 expression, left ventricular dysfunction, increased myocardial apoptosis and fibrosis. PHLPP1 inhibition alleviated cardiac dysfunction. Additionally, PHLPP1 inhibition significantly reduced HG‐induced apoptosis and restored PI3K/AKT/mTOR pathway activity in H9c2 cells. Furthermore, pretreatment with LY294002, an inhibitor of PI3K/Akt/mTOR pathway, abolished the anti‐apoptotic effect of PHLPP1 inhibition.

Conclusion

Our study indicated that PHLPP1 inhibition alleviated cardiac dysfunction via activating the PI3K/Akt/mTOR signalling pathway in DCM. Therefore, PHLPP1 may be a novel therapeutic target for human DCM.

A Review of Data of Findings on Night Shift Work and the Development of DM and CVD Events: a Synthesis of the Proposed Molecular Mechanisms

PURPOSE OF REVIEW

Night shift work has become highly prevalent in our 24/7 societies, with up to 18% of the US work force working alternate shift schedules. However, studies indicate that there may be adverse health effects of chronic night work across diverse populations. These effects are likely due to misalignment of the circadian system with work schedules, mediated by the system's primary marker melatonin as well as other downstream molecules.

RECENT FINDINGS

Melatonin has multiple biologic actions that are relevant to cardiometabolic disease, including modulation of oxidative stress, inflammation, and (via the melatonin receptor) vasoconstriction. Behavioral traits, such as chronotype and meal timing, have recently been shown to interact with the effects of night work on cardiometabolic health. Together with recent findings suggesting a role for circadian genes in cardiometabolic risk, the interactions of night shift work and behavioral traits are likely to facilitate novel treatment and prevention approaches for cardiovascular disease and type 2 diabetes, incorporating aspects of clock and timing.

Serum γ-glutamyltransferase level is associated with periodontal disease independent of drinking habits in Japanese adults

Background Non-alcoholic fatty liver disease is considered a hepatic manifestation of metabolic syndrome. Periodontal disease is a mild chronic inflammatory disease with systemic effects, and many studies have indicated an association between metabolic syndrome and periodontitis. In the present study, we investigated the relationship between periodontitis and liver biochemical parameters according to alcohol drinking habits through a cross-sectional study based on data from Japanese people in occupational settings. Material and Methods The subjects were 1510 employees (1218 males, 292 females, mean age 50.4 years) who underwent dental and medical checkups in 2012. Associations between the presence of periodontal pockets and serum levels of liver biochemical parameters were assessed. Results Alanine aminotransferase (ALT) and γ-glutamyltransferase (GGT) levels were higher in subjects with than without periodontal pockets. Multiple logistic regression analysis (adjusting for age, gender, cigarette smoking, and alcohol drinking habits, and components of metabolic syndrome) with GGT or ALT as the dependent variable revealed that there was a significant association between periodontal pockets and GGT (odds ratio, OR=1.48), but not ALT. Similar associations were observed when an analysis was performed according to the presence or absence of alcohol drinking habits; the OR was higher in subjects without (OR=1.84) than with drinking habits (OR=1.41). Conclusions The presence of periodontal pockets was associated with serum levels of GGT, a liver biochemical parameter, in Japanese adults with no drinking habit, suggesting that periodontal disease is associated with liver function, independent of alcohol ingestion.

Current trends in the monitoring and treatment of diabetic retinopathy in young adults

The diagnosis and treatment of diabetic retinopathy (DR) in young adults have significantly improved in recent years. Research methods have widened significantly, for example, by introducing spectral optical tomography of the eye. Invasive diagnostics, for example, fluorescein angiography, are done less frequently. The early introduction of an insulin pump to improve the administration of insulin is likely to delay the development of diabetic retinopathy, which is particularly important for young patients with type 1 diabetes mellitus (T1DM). The first years of diabetes occurring during childhood and youth are the most appropriate to introduce proper therapeutic intervention before any irreversible changes in the eyes appear. The treatment of DR includes increased metabolic control, laserotherapy, pharmacological treatment (antiangiogenic and anti-inflammatory treatment, enzymatic vitreolysis, and intravitreal injections), and surgery. This paper summarizes the up-to-date developments in the diagnostics and treatment of DR. In the literature search, authors used online databases, PubMed, and clinitrials.gov and browsed through individual ophthalmology journals, books, and leading pharmaceutical company websites.

Periodontal microcirculation in diabetics: an in vivo non-invasive analysis by means of videocapillaroscopy

Background

Diabetes mellitus is today considered a society-wide disease of a chronic/degenerative nature. Among the secondary effects of diabetes, the one that interests the dental surgeon most is diabetic parodontopathy. The aim of this study was to underline and objectify microcirculatory variations at a periodontal mucous level in type 2 diabetics.

Material/Methods

The study enrolled 80 subjects: 40 subjects with a diagnosis of diabetes mellitus type II (18 males and 22 females, between 44 and 85 years of age); and 40 healthy subjects (17 males and 23 females, between 44 and 78 years of age). All the subjects, both diabetic and healthy, were submitted to a videocapillaroscopic examination of the mucosa of the oral cavity.

Results

The measurements concerning the density (expressed in the number of loops/mm²) of the capillary loops presented differences between the healthy subjects and the diabetic subjects. The average periodontal capillary density (DC-P) was clearly superior in diabetic subjects (35.62±10.40 n°loop/mm²) compared to healthy subjects (17.55±3.88 n°loop/mm²). The statistical analysis was performed by means of the Mann Whitney test. The value of P (p=0.000000986), well below the level of significance, demonstrates the high significance of the results obtained.

Conclusions

The increase in capillary density could suggest the presence of active inflammatory phenomena or, more probably, a tendency to a greater susceptibility to inflammatory phenomena. Ultimately, this study shows that there is some peripheral damage to microcirculation at the masticatory mucous level in diabetic subjects and that such alterations can be instrumentally objectified and quantified through the videocapillaroscopic method.

The association of early atherosclerosis and retinopathy in adolescents with type 1 diabetes: preliminary report

Recent studies have shown a close correlation between advanced diabetic retinopathy and the late stages of atherosclerosis. The purpose of this study was to analyse the association between diabetic retinopathy and early atherosclerotic changes in adolescents with type 1 diabetes. We studied 28 adolescents with type 1 diabetes. Eight patients with nonproliferative retinopathy were compared with the remaining 20 patients, and with 11 healthy controls. The function of endothelium was assessed by measuring flow-mediated dilatation (FMD), the intima-media thickness (IMT) of the common carotid arteries and adhesion molecules (sICAM-1, sVCAM-1, sE-selectin). In the group with retinopathy FMD equalled 7.8+/-4.1% vs. 12.1+/-5.1% in the control group (p=0.04), and in the group without retinopathy, 7.6+/-5.5% (p=0.04 compared to controls). Higher IMT was found in all patients with diabetes in comparison with healthy controls: 0.49+/-0.06 mm vs. 0.42+/-0.03 mm (p=0.001). Patients with retinopathy had a significantly higher value of IMT in comparison not only with controls but also with patients without complications: 0.56+/-0.06 mm vs. 0.47+/-0.03 mm (p=0.0001). Adhesion molecule levels were not changed in patients with retinopathy. Higher IMT was found in adolescents with diabetic retinopathy in comparison with patients without complications, which may suggest that macrovascular changes are more advanced in these patients than in their diabetic peers without retinopathy.

Buscando mobilizar-se para a vida apesar da dor ou da amputação

OBJETIVOS: compreender como o paciente lida com as conseqüências da Doença Arterial Obstrutiva Crônica. MÉTODOS: utilizou-se o referencial teórico do Interacionismo Simbólico e a Teoria Fundamentada nos dados como referencial metodológico. Dez portadores desta doença foram entrevistados e, seus relatos analisados segundo a técnica da análise comparativa dos dados que permitiram compor três fenômenos. RESULTADOS: evidenciou-se três fenômenos: Tendo a vida restrita pela dor, Sentido-se condenado e Buscando retornar à vida. O elemento central que subsidia as decisões, sentimentos e comportamentos indica que o paciente está sempre, simbólica e concretamente, BUSCANDO MOBILIZAR-SE PARA A VIDA APESAR DA DOR OU DA AMPUTAÇÃO. CONSIDERAÇÕES FINAIS: Os resultados permitem ampliar a compreensão da experiência do paciente, agregando conhecimentos para que o enfermeiro tenha mais subsídios para avaliar clinicamente e, assim atuar com maior adequação em relação aos aspectos psicosociais.

Peripheral arterial disease in diabetic patients selected from a primary care setting: Implications for nursing practice

Although the care of patients with diabetes is increasingly provided in primary care, there is relatively little information on the prevalence and long-term progression of asymptomatic peripheral arterial disease (PAD) in diabetic populations selected from primary care settings. The aims of this study were to investigate prevalence and progression of PAD in 146 diabetic patients, and to compare mortality with 113 nondiabetic controls over a 7-year period. The prevalence of PAD in individual pedal arteries varied between 28.6% in the right posterior tibial artery to 48.8% in the left peroneal artery. During the 7-year period, 34.25% of the diabetic subjects died, and 17.5% moved to other locations. Of the remaining 70 patients, 35 (50%) showed no change in ankle-brachial index and 35 (50%) did show change. Comparison of risk factors between those who did and did not show evidence of progression revealed (1) a strong, significant, independent association between hyperglycemia (measured by plasma HbA1c) and progression of PAD among the diabetic population; and (2) a strong association between progression of the disease and family history of diabetes and ischemic vascular disease. There was a high death rate (34.25%) among the diabetic group, which was greater than for the age- and sex-matched nondiabetic controls (13.2%) drawn from the same practice. This high mortality was significantly related (P < .001) to the presence of PAD identified during first-year assessment. Once PAD develops in association with diabetes the long-term prognosis is poor and carries a high mortality rate mainly because of cardiovascular and cerebrovascular diseases. Both progression and mortality were significantly related to poor diabetic control. The role of the primary care nurse in assessing such patients by using Doppler-assisted measurements is one that should be expanded with the massive increase in the number of diabetic patients in the coming years.

Glycaemic control is essential for effective cardiovascular risk reduction across the type 2 diabetes continuum

The growing prevalence of diabetes, an established risk factor for cardiovascular disease, threatens to significantly increase the global burden of cardiovascular morbidity and mortality. The risk of cardiovascular mortality is substantially higher in individuals with early glucose intolerance than in those with normal glucose levels and the pathological changes in vascular function begin many years before the diagnosis of overt type 2 diabetes. Postprandial hyperglycaemia is particularly deleterious to vascular function, and impaired glucose tolerance (IGT) - but not impaired fasting glucose - and may be an independent risk factor for cardiovascular disease throughout the glucose intolerance continuum. Evidence that molecular mechanisms induced by postprandial hyperglycaemia contribute to vascular damage has further highlighted the importance of targeting this component of the metabolic syndrome. Indeed, clinical trials have failed to convincingly show that interventions targeting fasting hyperglycaemia significantly reduce diabetes-associated cardiovascular risk. It may be necessary to refocus therapy to target postprandial hyperglycaemia to effectively reduce cardiovascular risk in the diabetic population. There is now direct evidence that pharmacological intervention, in the form of acarbose, to reduce postprandial hyperglycaemia, can significantly decrease the risk of cardiovascular events in individuals with IGT or type 2 diabetes.